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Opening a Port

I have an application that is having troubles transmitting over the internet and I suspect it's a firewall/ports issue. I had someone with domain admin rights log in and test the same app and the had the same problems. They tell me that with their credentials that they have access to all ports and that something else other than a port problem would be the problem. I thought that if a port is closed, it is closed to everyone regardless of their credentials. Can someone confirm my suspicion though that a port is closed regardless of your login credentials?

Reply to
Kristen Salerno
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A port on a FW is open under two conditions that I know about.

1) The admin of the FW did a port forwarding of a port or ports (opening ) it or them to unsolicited inbound traffic from the Internet, such as a WEB server sitting there listing for unsolicited inbound traffic from client machines with an browser on port 80, as an example. That would mean something behind the FW, a program running on a computer, was sitting there listing on its port or ports for unsolicited inbound traffic from the Internet.

2) Any program running on a machine behind the FW that sends outbound traffic to a remote IP, a solicitation of traffic by the program, the FW will open the required inbound port or ports back to the soliciting program, like your machine that's has a browser and you make contact with a WEB site. The FW is going to allow the solicited inbound traffic back to your machine, on port 80.

Admin rights on a machine or a Domain has nothing to do with it that I know about.

Duane :)

Reply to
Mr. Arnold

Too little detail. Too much hearsay.

- What application? Version?

- What kind of transmission? Protocol? Data?

- What's the exact error message?

- Have you some sort of packet filter on the host in place?

- What firewall do you use?

- What do the logs on the host say?

- What do the logs on the firewall say?

- Have you tried the respective network tools (ping, netstat, traceroute, port scanner, sniffer, ...) to track down the issue? What were the results?

cu

59cobalt
Reply to
Ansgar -59cobalt- Wiechers

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